FIG. 1 illustrates two known ways of locking the passive door of a double door. The double door consists of an active door blade 1 and a passive door blade 2. The active door blade and the passive door blade are also called the active door and the passive door. The active door blade is the door for normal usage, used when the doorway is passed through when not carrying larger loads. In case larger items must be transported through the doorway, such as during moving, opening the active door blade does not necessarily form a large enough opening. In such case the passive door blade is opened as well. Usually the passive door blade is locked to the jamb structure 4 of the doorway and the floor level 3.
The active door blade 1 and the passive door blade 2 are rotatably attached to the jamb structure 4 of the doorway by means of hinges. Usually the active door blade 1 comprises a lock 5 comprising a bolt 6. When the active door 1 is locked, the bolt 6 is partially inside the striker lock body 7, thus locking the active door to the passive door. The striker lock body is also called a striker lock and vice versa, because in practice the body comprises the lock functions. Because the passive door 2 is locked to the jamb structure 4 of the doorway and the floor level 3, the passive door cannot rotate and neither can the active door locked to the passive door. It can be said that in normal use the passive door is a part of the jamb structure of the doorway 4. The locking of the active door 1 is released normally and the door is opened normally.
The striker lock body 7 is combined with pull bars 9, 10 installed in the passive door 2 and locking the passive door to the jamb structure of the doorway and the floor. Recesses 12, 11, into which the ends of the pull bars are located when the passive door is locked, are arranged in the jamb structure 4 and the floor level 3. A release means 8 is arranged in the striker lock body for pulling the pull bars towards the inside of the passive door so that the ends of the pull bars move away from the recesses 11, 12 of the frame structure and the floor level. The name of the pull bars is derived from this action. When the pull bars are pulled inside the passive door, the passive door can be opened, i.e. rotated. A typical release means 8 comprises a hand-turnable lever. In some known solutions the release means 8 is not located in connection with the striker lock body of the passive door but instead it is formed as a separate unit being in connection with the pull bars. The pull bars can also be moved back to the protruding position away from the inside of the passive door by means of the release means 8, whereby the passive door can be locked back to the jamb structure and the floor level.
Another way of locking the passive door is by using separate locks in the upper edge and/or lower edge of the passive door blade. FIG. 1 illustrates an embodiment in which both the upper edge and the lower edge of the passive door blade comprise a lock 13. The lock comprises a latch 15 that is in protruded position when the door is locked. The latch of the upper lock 15 locks the passive door to the frame 4 while the latch 15 of the lower lock locks the door to floor level 3. The locking of the doors is released when the active door blade is opened, whereby the control wedge 14 of the lock 13 can move out. The protrusion of the control wedge directs the latch 15 to the inside of the lock, whereby the passive door can be opened. The locking is effected when the active door is turned against the passive door, whereby the control wedge is depressed to inside the lock and simultaneously directs the latch 15 from the lock.
The problem with the upper and lower lock is that the control wedge 14 resists closing and opening the active door. The lock 13 has a spring/a spring system pressing the control wedge out from the lock. The control wedge then presses the active door. This reduces the ease of use of the active door. Further, if the active door is combined with door automatics, the lock 13 can also resist the operation of the door opening/closing apparatus.
Patent publication WO 2006117457 also discloses a known method for locking the passive door blade of a double door. The solution of the publication shows a design in which the ends of the pull bars (cf. FIG. 1) are provided with a locking bolt system. When the pull bar is pulled inside, the bolt can turn and the passive door can be opened. The end of the pull bar is also provided with a spring pushing the pull bar outwards. When the passive door is closed, the bolt turns and the spring can push the bolt outwards to locking position. Installing this solution is fairly difficult, as the pull bar must be cut quite precisely before installation and it is fastened to the locking bolt system before installation. The pull bar must also be removed from the passive door in connection with any service work or replacement.